1. Field of the Invention
This invention relates to hand tools, and more particularly to improved hand tool construction and method of expanding hollow wall anchors.
2. Description of the Prior Art
It is known to utilize hollow wall anchor elements to adapt plaster or dry walls to support cabinets, shelves and the like. A widely used wall anchor for this purpose is formed from a hollow sleeve with a flange at one end to seat against the inner surface of a wall, and which at its opposite end is threaded to receive the inner end of a threaded bolt. The body of the sleeve intermediate its end portions has spaced longitudinal slots, thereby forming the body as a cage of thin ribs--usually three in number. The bolt in an assembled anchor is threaded in so the bolt head bears against the flange. The inner end of the bolt may extend through the threaded end of the sleeve to threadedly engage a coned element which, together with a pointed end for the bolt, facilitates driving the anchor through a wall. Alternatively, holes may be drilled in the wall to slidably receive such anchor elements.
Such wall anchors as heretofore employed are intended to be inserted through walls with their flanges seated against the inner surface of such a wall. Thus positioned, anchoring of each element is effected by turning the bolt head against the flange with a screwdriver so as to draw the threaded end of the anchor towards the wall. Such movement is facilitated by deformation of the ribs, which are forced into the wall material to interlock therewith.
Heretofore, such wall anchors have not been useful in situations where they cannot be driven or inserted through a wall so that, initially, their flanges are seated against the inner wall surfaces. Where the inner ends of such anchors are obstructed, e.g., as by coming against a concrete pillar or wall located behind the plaster or dry wall into which they are driven, their flange ends are spaced from the inner surface of the plaster. Accordingly, turning of the threaded bolt cannot effect action of the parts of the anchor element as required to anchor it in the wall material. Where the structural strength of such an anchor is required at that type of location, resort must be to a different type of support, e.g., toggle bolts, having the desired strength but requiring substantially different operations to effect their use. Further, such situations cause undesired delays in determining that a given anchor cannot be used and that a different type of support must be found and used in lieu thereof.